Isopeptidase T regulation of Ubiquitin System

异肽酶 T 对泛素系统的调节

• 批准号: 6987192
• 负责人: Francisca E. Reyes Turcu
• 金额: $ 2.8万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6987192
• 关键词: SDS polyacrylamide gel electrophoresis; X ray crystallography; atomic absorption spectrometry; binding sites; enzyme activity; fluorescence polarization; fluorescent dye /probe; ion exchange chromatography; molecular shape; peptidases; predoctoral investigator; protein binding; protein isoforms; protein localization; protein metabolism; site directed mutagenesis; ubiquitin

DESCRIPTION (provided by applicant): Covalent attachment of ubiquitin, either as a monomer or as a polymer (polyubiquitin chains), serves as a signal that regulates the location, activity and/or degradation of many proteins. After serving as a signal polyubiquitin must be processed to monoubiquitin to maintain ubiquitin homeostasis. Isopeptidase T (IsoT) is a specialized deubiquitinating enzyme responsible for the regeneration of monoubiquitin from polyubiquitin chains. This role makes IsoT a central regulator of the ubiquitin system. The goal of this proposal is to understand how IsoT binds multiple isoforms of polyubiquitin chains by: 1) testing the polyubiquitin chain isoform binding selectivity of Isot; 2) determining how each of the four ubiquitin binding domains of IsoT contributes to the recognition of polyubiquitin chains; and 3) obtaining a molecular description of the recognition of polyubiquitin chains by IsoT using X-ray crystallography. Determining the substrate preference of IsoT and which domains are involved in binding each polyubiquitin chain isoform will provide insight into the general mechanism of polyubiquitin chain recognition and may aid in the development of pharmacological effectors of the ubiquitin system.

描述（由申请人提供）：泛素的共价附着，无论是单体还是聚合物（聚偶像素链），是调节许多蛋白质的位置，活性和/或降解的信号。用作信号多泛素后，必须将其加工到单纤维素中以维持泛素稳态。等肽酶T（ISOT）是一种专门的去泛素化酶，负责从多泛素链中再生单喹啉的再生。该角色使ISOT成为泛素系统的中心调节剂。该提案的目的是通过以下方式了解ISOT如何结合多泛素链的多种同工型，1）测试ISOT的多偶联蛋白链同工型的选择性； 2）确定ISOT的四个泛素结合结构域中的每一个如何有助于识别多泛素链； 3）通过使用X射线晶体学来获取对多泛素链识别多泛素链的分子描述。确定ISOT的底物偏好以及哪些域与结合每个多泛素链的同工型结合，将洞悉多泛素链识别的一般机制，并可能有助于开发泛素系统的药理学效应子。